1. Field of the Invention
The invention relates to a gripper weaving machine comprising at least one rapier carrying a gripper and being moveable into and then out of a shed by a drive wheel and being guided outside the shed by guide elements that maintain the rapier in contact against the drive wheel and in alignment with the shed.
2. Description of the Related Art
U.S. Pat. No. 5,413,151 discloses a gripper weaving machine wherein a filling thread is inserted into a shed by two grippers each affixed to a flexible rapier. A feed gripper moves the filling from one side of the shed to about its middle where it is transferred to a receiving gripper which thereupon carries this filling to the opposite side of the shed. Each rapier is moved by a drive wheel into and out of the shed. Guide elements located outside the shed guide the rapier between the drive wheel and the shed. These guide elements keep the rapiers in contact with the drive wheel and in alignment with the shed. Guidance devices are mounted on the batten and can be moved into and out of the shed for guiding the rapiers within the shed. When a rapier enters the shed, the batten together with its affixed guidance devices are situated in a rear position in order that these guidance devices (which are now inside the shed) are able to receive the rapier from the guide elements mounted adjacent to the shed.
As regards such gripper weaving machines, the position of the rapier within the shed is determined essentially by the arrangement of drive wheels on the frame of the gripper weaving machine. The angle subtended between the drive wheels and the frame and the geometry of the shed conventionally are selected in such manner that the rapier shall assume a position within the shed whereby the largest possible number of different warps and fillings can be woven together without incurring unduly numerous thread ruptures in the vicinity of the guide elements that are moved into and out of the shed. However setting the drive-wheel angle of a gripper weaving machine restricts the number of possible warps and fillings that may be woven together. Once the angle at which the drive wheels are mounted on the frame has been set, it is subsequently practically impossible to change the same in a gripper weaving machine.